Update audio code to use size_t more correctly,

webrtc/modules/audio_coding/main/test/SpatialAudio.cc

Index: webrtc/modules/audio_coding/main/test/SpatialAudio.cc
diff --git a/webrtc/modules/audio_coding/main/test/SpatialAudio.cc b/webrtc/modules/audio_coding/main/test/SpatialAudio.cc
index b28c510a56617a4ca9a12bee0aec40f50a454c6a..134d9755e5dc312219a5fd9c3e196aa079f99530 100644
--- a/webrtc/modules/audio_coding/main/test/SpatialAudio.cc
+++ b/webrtc/modules/audio_coding/main/test/SpatialAudio.cc
@@ -159,13 +159,13 @@ void SpatialAudio::EncodeDecode(const double leftPanning,
 
   while (!_inFile.EndOfFile()) {
     _inFile.Read10MsData(audioFrame);
-    for (int n = 0; n < audioFrame.samples_per_channel_; n++) {
+    for (size_t n = 0; n < audioFrame.samples_per_channel_; n++) {
       audioFrame.data_[n] = (int16_t) floor(
           audioFrame.data_[n] * leftPanning + 0.5);
     }
     CHECK_ERROR(_acmLeft->Add10MsData(audioFrame));
 
-    for (int n = 0; n < audioFrame.samples_per_channel_; n++) {
+    for (size_t n = 0; n < audioFrame.samples_per_channel_; n++) {
       audioFrame.data_[n] = (int16_t) floor(
           audioFrame.data_[n] * rightToLeftRatio + 0.5);
     }